1. Field of the Invention
The present invention relates to a clamping jaw, and to a clamping element for use in the clamping jaw.
2. Description of the Prior Art
A clamping jaw is disclosed in EP 1693153 A2, in the surface of which semicircular recesses are machined. Round clamping elements are inserted in the recesses, which are thus mounted in a rotating arrangement in the recesses and project therefrom in part. Clamping pins, tapering to a point, are provided on the surface of the clamping element facing towards the workpiece to be clamped, whereby the clamping pins act on the workpiece in the clamped condition, penetrating into the workpiece, given appropriate clamping force, and effecting a plastic deformation in it, as a result of which a positive active connection is established between the clamping elements and the workpiece. The clamping elements are arranged on the top side of the clamping jaw, and project outwards from the top side plane.
The ability of the clamping elements to rotate in the corresponding recess are adapted to effect an alignment of the corresponding clamping elements with regard to the outer contour of the workpiece to be clamped, in order to achieve a reliable and durable positive connection between the clamping elements and the workpiece during the clamped condition.
However, the clamping elements are mounted in a rotating arrangement in the recesses, which means that there is a disadvantage that a significant clamping force must be exerted in order to achieve any reliable clamping, as well as plastic deformation, because the clamping pins are pushed away from the workpiece as soon as the clamping pins come into active contact with the workpiece. As a result, each clamping situation leaves the impression of a different clamping pin on the workpiece. This impression arises practically indiscriminately, which means that it cannot be used further during unclamping and re-clamping in order to clamp the workpiece in a different machine tool. As a result, damage to the workpiece increases with the number of clamped conditions.
Furthermore, the clamping elements are arranged at a clamping height of about 10 millimeters in order to be able to transmit any clamping forces whatsoever onto the workpiece. Consequently, the workpiece is damaged at this clamping height. This refers to the clamping height from a lower edge of the workpiece to the level of the highest clamping height.
AT 389270 B discloses a clamping fixture with two clamping jaws movable towards one another. Triangular clamping elements are provided on the upper side of the clamping jaws. Clamping elements running adjacent to one another form a common plane with their end surface that faces towards the workpiece.
These clamping elements provide a clamping surface in, or on which, no clamping pins, clamping pegs, or the like, disposed, as the result of which an exclusively friction-locking active connection is produced between the clamping elements and the workpiece to be clamped.
The task of the present invention is therefore to improve a clamping jaw, or a clamping element, of the aforementioned types such that the clamping height of the clamping elements can be reduced to 3.5 millimeters, or less, without sacrificing reliable and durable active connection between the clamping elements and the workpiece clamped. Furthermore, by means of the clamping elements, it is possible to achieve an even profile of indentations in the workpiece, as a result of which identically configured clamping pins and clamping elements will engage in the already existing indentations in the workpiece in order to allow the workpiece to be attached in precisely the previous position on several different machine tools without requiring additional indentations in the workpiece. Also, the clamping force to be applied can be transmitted onto the workpiece such that the clamping elements are held on the clamping jaw with as little play as possible, such that there is no slippage or rotation when active contact is made with the workpiece.